[WIP] Add a (jaccard) similarity method to nodegraph and bitstorage

[luizirber]

• [ ] Is it mergeable?
• [ ] make test Did it pass the tests?
• [ ] make clean diff-cover If it introduces new functionality in scripts/ is it tested?
• [ ] make format diff_pylint_report cppcheck doc pydocstyle Is it well formatted?
• [ ] Did it change the command-line interface? Only backwards-compatible additions are allowed without a major version increment. Changing file formats also requires a major version number increment.
• [ ] For substantial changes or changes to the command-line interface, is it documented in CHANGELOG.md? See keepachangelog for more details.
• [ ] Was a spellchecker run on the source code and documentation after changes were made?
• [ ] Do the changes respect streaming IO? (Are they tested for streaming IO?)